A common problem for operators of heavy equipment, and other powered machinery, is cold weather starting of internal combustion engines, particularly diesel engines. In many cases, such as logging operations, rural road construction, or outlying farming operations, enclosed storage is nonexistent, or impractical. The resultant exposure of equipment to cold ambient temperatures during prolonged nonoperative periods tends to increase oil viscosity, reduce battery output, and makes the vaporization of fuel much more difficult. These effects combine to make cold weather starting of engines a prolonged and difficult task. In addition to the increased wear of batteries and starting motors, cold starts greatly increase the wear of internal engine components, due to poor initial lubrication. The common use of electric block heaters is often not possible, due to the lack of suitable electrical power.
A number of fuel gas fired engine preheaters have been proposed as a solution to the cold weather starting problems of internal combustion engines. These are exemplified by U.S. Pat. Nos. 3,131,864 to Young; 3,400,700 to Lindsey and Klancke (1968); 4,348,992 to Southard (1982); and 4,520,769 to Kratzer (1985). These inventions have not found wide spread use due to a number of limitations and problems in their operation.
A primary limitation of the prior art has been a lack of automatic controls to allow the engine heating apparatus to operate in a safe reliable manner, without the requirement of an external electrical power source. A further disadvantage has been relatively inefficient heat transfer from the ignited fuel heat source to the engine coolant. There has also been no viable method to enable a single self-contained engine heater to preheat a number of different engines at various times and at various locations.